Hone gauging device



Aug. 8, 1944. R. MEsTAs r 2,355,316

' .HoNE GAUGING DEVICE Filed Aug. V1'. 1940 2 Sheets-sheet 1 1i' N l /54 ,z

A TTC/@vens Patented Aug. 8, 1944 HONE GAUGING DEVICE Ricardo Mestas, Los Angeles, Calif., assignmto Kobe, Inc., Huntington Park, Calif., a corpora.-

tion of California Application August 3, 1940, serial No. 350,941

1 claim.

My invention relates to honing devices, and more particularly to a honing device having gauge means provided to indicate the progress of the honing operation.

My invention is of particular utility in honing the interior of a tubular member, such as, for example, a piston cylinder, to a very close tolerance, and, consequently, for' the purpose of illustration will be described in connection with such a use, although it will be appreciated that my device may be'utilized in honing any kind of work as may be desired without departing from the spirit of my invention.

In honing a surface, and particularly the interior surface of a tubular member, it is standard practice to work a honing device on the sur--` face 'for a period of time, then withdraw the honing device, and then apply a gauge to the surface to determine the progress of the honing operation. Where it is required to hone or finish a surface to close tolerances, this standard practicevofV Working requires many time consuming gauging operations which are uneconomical and undesirable. Another disadvantage is that when the honing device must be withdrawn from the surface being honed to permit the gauging operation, as is frequently the case where the interior surface of a tubular member is being finished, it is sometimes diflicult to re-engage the honing device with the surface being worked in exactly the same position as it occupied relative thereto prior to the gauging operation, thus causing unevenness in the subsequent honing operation. To obviate these disadvantages, it is a primary oblect of my invention to provide a method and apparatus for honing in which the extent of the honing operation may be measured and gauged during the honing operation and Without withdrawing the honing device from the surface being honed. I prefer to accomplish this by providing a honing device having Va gauge incorporated directly therein, with indicating means provided to indicate to an operator, in response to operation of the gauge, the progress of the honing operation.v

It is also an object of my invention to provide a, honing device having a gauge incorporated therewith for gauging the progress of the honing operation on a surface to be honed, and having an indicating means provided at a point remote from the honing device and operating in response to the operation of the gauge to indicate at the remote point the progress of the honing operation. t

A further object of the invention is to supply a device of the character specified in the preceding paragraph, in which the indicating means is connected to the gauge by electrical means and operated thereby.

Still another object of my invention is to provide a honing device having an electrical gauge means incorporated' therewith adapted to operate in response to changes in a magnetic iiux through a member formed of magnetic material 'being honed, caused by progress of the honing operation, to indicate the progress of `the honing operation. i

A further object of my invention is to provide a honing device for honing a non-magnetic material, having a gauge associated therewith operating in response to progress of the honing operation to indicate on a suitable indicating means during the progress of the honing operation the extent thereof.

Other objects and advantages will be apparent from the following specification and the drawings, which are for the purpose of illustration only and in which:

Fig. 1 is a vertical elevational view of my invention partly extending linto a tubular member to be Worked.

Fig. 2 is an enlarged cross-sectional view taken on the line 2-2 of Fig. l.

Fig. 3 is a longitudinal sectional View taken on the line v3--3 of Fig. 2.

Fig. 4 is a diagrammatic view of the electrical circuit utilized in my device.

Fig. 5 is a llongitudinal sectional view of an alternative embodiment of my invention.

Fig. 6 is a cross-sectional view taken on the line 6 6 of Fig. 5.

Referring to Figs. 1, 2, and 3 of the drawings,

"I show a tubular member III having a bore II therethrough, such as, for example, a pump cylinder, it being necessary to hone or otherwise grind the surface of the bore II to a desired diameter within c lose tolerances. Extending into the bore II of the tubular member I0 is a honing device I2. y

The honing device I2 includes a head member I3 having a major bore Il and a threaded minor bore I5 separated by a partition I6. Formed in the head member I3 so asto communicate with the major bore M thereof are a plurality of hone -slots I1 radially disposed therein and preferably spaced equidistantly around the periphery ot the head member. Also formed in the head member I3 are a pair of diametrically opposite gauge slots I8, each of which, as shown, is formed .between adjacent hone slots Il. Disposed in each'of the hone slots l1 is a hone box I9 of approximately the same cross-sectional conguration as the hone slots but forming a relatively loose nt therein so as tobe radially movable therein, each hone box I9 having a recess 20 therein in which is suitably secured a hone element 2I formed of carborundum or other suitable grinding material. As will be noted, each'hone box I9 is provided with asloping inner face 22, and all of the hone boxes I9 are yieldably restrained against outward radial movement relative to the head member I3 by upper and lower annular springs 23 and 24, respectively, engaging the outer surfaces of all of the hone boxes and being received in annular recesses 25 formed in the head member I3.

Received in the gauge slots I8 of the head member I3 are gauge boxes 21 and 28, respectively, which are preferably press-fitted or otherwise rigidly secured relative to the head mermber, andsince the gauge boxes are identical in construction, only the gauge box 21 will be described in detail. The gauge box 21 is provided with a central opening 29 within which is positioned a U-shaped core 39 formed of magnetic material, on the upper leg ,of which is provided an upper winding 3| and ron the lower leg of which is provided a lower winding 32, which windings are connected in series to form a nirst winding means 26. Inset in the outer face of the gauge box 21 in a suitable recess 33 is a closure member 34 formed of substantially nonmagnetic material, such as aluminum, which is rigidly secured relative to the gauge box, as by a pressfit. As will be noted, the U-shaped core 36 is positioned in the opening 29 so that the outer ends of the legs thereof almost engage the closure member 34. The gauge box 28 is provided with a second winding means 35 which is identical in construction with the first winding means 26 of the gauge box 21. The upper and lower windings 3l and 32 of the rst winding means 26 are in series with each other and are connected in series through a conductor 36 with the coils of the second winding means 35 of the gauge box 28, which are also connected in series, and which are in turn connected to a lead-in wire 31. The other end of the rst winding means 26 is connected to a lead-in wire 38. The conductor 36 and the lead-in wire 38 pass through a hold 39 drilled in the end of the gauge box 21, and the lead-in wires 31 and 38 pass outwardly from the major bore I4 through a hole 40 drilled in the head member I3 into a longitudinal channel 4I formed threin. As will be noted, when the head member I3 is disposed within the bore II, the closure members 34 will be slightly spaced from the bore II, forming air gaps 42 and 43 therebetween ad- `jacent the outer ends of the legs of the cores of the first and second winding means 26 and 35. The air gaps 42 and 43 are variable in length, the same increasing as the honingoperation, described hereinafter, progresses.

Received in the major bore I4 is a plunger member 44 having a rod 45 formed thereon which passes upwardly through the partition I6. The plunger member 44 is provided with a pair of longitudinal channels 46 therein, which are oppositely disposed and which nt around the gauge boxes 21 and 28, respectively, the channels being rectangular in cross-sectional configuration. Alsoformed in the plunger member 44 are hone box channels 41, each of which fits around one of the hone boxes I9, and each of which is provided with an irmer face 48 which is tapered to cooperate with the sloping inner face 22 of the corresponding hone box. Thus, downward movement of the plunger member 44 will cause each of the hone boxes I9 to move radially outwardly in its hone slot I1, to engage the bore II of the tubular member I0. Formed in the rod is a longitudinal groove which receives the inner end of a screw pin 5I threaded into a threaded opening 52 formed in the head member I3, the screw pin and thergroove cooperatingto form a stop means limiting axial movement of the rod Threaded into the threaded minor bore I5 of the head member I3 is a tubular sleeve 54 having a longitudinal groove 55 cut therein to receive the lead-in wires 31 and 38, the upper ends of which are electrically connected to a suitable slip ring mechanism 56 adapted to be engaged by electrical contacting brushes (not shown), as is will known in the art, to form an electrical takeoi for the lead-in wires. The slip ring mechanism 56 is carried on the upper end of the tubular sleeve 54. Provided on the tubular sleeve 54 is a collar 51 having a pin 51h therein which extends through a suitable hole in the sleeve into a plug 51c journalled therein, through which slidably passes a rod member 58, the lower end of which is threaded into the upper end of the rod 45, and the upper end of which passes outwardly through the upper end of the sleeve 54, there being a compression spring 59 positioned around the rod member 58 and engaging the rod 45 and the plug 51e. The compression spring 59 is set under compression so as to normally urge the plunger member 44 downwardly to move the hone boxes I9 outwardly into engagement with the bore I I of the tubular member I9 against the action of the annular springs 23 and 24. By raising the rod member 58 against the action of the compression spring 59, however, the plunger mem-ber 44 will be moved upwardly so as to permit the annular springs 23 and 24 to retract the hone boxes I9 into the head member I3.

During operation, thetubular sleeve 54 is rotated or reciprocated, or both, by any suitable means (not shown) and, since the hone boxes I9 are forced outwardly by the plunger member 44, the hone elements 2| are maintained in pressure engagement with the wall of the bore `II of the tubular member I0 by the action of the compression spring 59, causing honing of the bore as a consequence, which constitutes the honing operation of my device. As the honing operation progresses, the length of the space in the air gaps 42 and 43 between the closure members 34 and the bore II will increase, as described. If an al- ,ternating current potential is'impressed across the series-connected rst Winding 26 and second winding 35, it will be clear that a magnetic circuit Will be established through the U-shaped core 30, the closure member 34, and the tubular member Il! being worked, and that as the distances across the air gaps 42 and 43 become progressively greater with increased honing, the reluctance of the magnetic path will increase and the impedance of the series-connected windings 26 and 35 will vary proportionally.

This cha-nge in impedance ofthe series-connected windings 26 and 35 can be indicated at a remote point by use of a suitable electric circuit and -a suitable indicating means. The circuit shown in Fig. 4 has been found to bevery satisfactory. Referring thereto, the series-connected windings 26 and 35 are connected in series with a variable impedance across a source of alternating potential of suitable frequency, indicated at 66. The variable impedance 65 can be positioned at a point remote from the series-connected ndings 26 and 35, and only the lead-in wires 31 and 38 need extend to the honing device. The variable impedance 65 may comprise a variable resistance, although I prefer to use a variable reactance having an impedance of the same order as the series-connected windings 28 and 35, so that the current and voltage in the two portions of the output circuit (to which the impedance 65 and the windings 26 and 35 are respectively oonnected as will be described) will have substantially the same phase relationship. The variable impedance 65 serves as an adjustment for the circuit, as will be described hereinafter.

A primary winding 61 of-a transformer 68 is connected across theseries-connected windings 26 and 35, and a similar primary winding 69 of a transformer is connected across the variable impedance 65. Ihe transformer 68 provides a secondary winding 1| which substantially matches in impedance a suitable rectifier 12 which is connected to one terminal thereof, the other terminal being connected to a conductor 13 and to one terminal of a secondary winding 1I of the transformer 10. The impedance of this windingl matches that of a rectifier 15. In some instances, the transformers 68 and 10 can be eliminated in favor of a direct connection between the rectiiiers'12 and 15 and the series-connected windings 26 and 35 and the variable impedance 65. In this event, the impedance of the series-connected windings 26 and 35 and the impedance of the variable impedance 65 should substantially match the impedances of the rectifying circuits to which they are connected. The output of the rectifying means comprising the rectiiiers 12 and 15 as shown in Fig. 4 as being delivered to a resistor 16, the center tap of which is connected to the conductor 13. By-pass or filter condensers 11 and 18 may be connected across the halves of the resistor 16 to filter out the peaks and valleys of the rectiiied current.

The resistor 16 is connected to the input circuit of a suitable amplifier means. This should preferably be of the ortho-ampliiier type for reasons to be hereinafter described. Fig. 4 shows dia# grammatically a single-stage amplifier including a pentode tube 80, the grid 8| of which is connected to one terminal of the resistor 16,

A source of direct current potential is indil cated as being applied across a voltage-dividing deviations in one direction will indicate a diameter smaller than the calibrated standard, and deviations in the other direction will indicate a diameter larger than the calibrated standard. As the deviations produced are linear and proportional to the diameter of the bore Il, linear calibrations can be placed on the galvanometer 36 to obtain accurate indications of the diameter of the bore at any time during the honing.

As honing progresses during the honing operation, the potential input to the pentode tube 80 may not vary exactly proportionally with respect to changes in diameter of the bore, due to the fact that the construction of the control unit may be such that' the potential across the seriesf connected windings 26 and 35 will not be directly resistor 82. A movable contact 83 serves to connect one terminal of the resistor 16 to the resistor 82. A cathode 84 of the pentode tube 80 is shown as being of the indirectly heated type and is tapped into thenresistor 82 at a. point of appropriate potential, as is also a grid means 85 which may comprise the conventional screen grid. A plate 86 of the tube is connected by a conductor 81 to one terminal of a resistor 88, the other terminal of which is connected to the positive side of the direct current source, as indicated.

A suitable potential-responsive indicating means is connected to the output of the amplifier. This may comprise a galvanometer 90 con 65 because it can be balanced to a zero reading and a pointer 92 thereof will deviate from this zero, reading proportionally to the changes in diameter of the bore Il produced by the hone. Furthermore, this deviation will be directional in that proportional to changes in diameter, or due to other factors. The galvanometer 30 can be calibrated to compensate for this slight non-proportionality, but it is preferred to use a linearly calibrated meter and compensate for such slight non-proportionality by design of the amplifying unit, shown as comprising the tube 80. By proper design of the amplifier and by proper selection of the applied potentials, a characteristic ampliiier curve can be obtained which, in the operating range of the device, will compensate for any non-proportionality and deliver an output potential which varies proportionally with the size of the bore I produced by the honing operation.

In using the device, the input to the tube is first disconnected and the galvanometer 36 brought to a zero reading by adjustment of the variable contact 9|. The input is then connected and the device is tested to be sure that displacements of the 'pointer 82 -of the galvanometer 30 will vary proportionally with changes in diameter. 'I'his test can be made by inserting the hone in rings of known internal diameter.

and if the pointer 32 does not move proportionally, suitable adjustment is made; for example, the movable contact 83 may be adjusted, or other potentials applied to the tube may be varied. 'I'he hone is then inserted in a ring of known internal diameter, for example, having the diameter of the bore which it is desired to obtain from the honing operation,'and the variable impedance 65 is adjusted to bring the pointer l82 to a ldesired point, for example a zero reading. The

device can then be inserted into the bore to be honed, and the galvanometer will indicate the deviation from the desired diameter in the vicinity of the hone elements 2|, and honing can -be eiected until the galvanometer indicates that the desired diameter has been reached.

The electrical circuit shown in Fig. 4 is more fully described and claimed in my copending application, Serial No. 350,939, led August 3, 1940, to which reference is hereby made for a better understanding of the operation and control of such a circuit.

Since the cores 30, on which the windings 26 and 35 are placed, are diametrically disposed, the head memberV I3 need not be accurately aligned axially with the axis of the bore of the tubular member |0`to be honed, as errors in centering will be substantially cancelled by an increase in impedance of the windings 26 and a corresponding decrease in impedance of the windings 35, or vice versa, which is another important feature of my invention. It is also to be noted that the device shown in Figs. l, 2, and 3 will operate only where the tubular member I0 is formed of magor material which issubstantially. non-magnetic, an alternative embodiment of my invention, de scribed hereinafter, may be used.

Referring to Figs. and 6, I show an alternative form of gauge mechanism for use in my honingv device, which is operated by a suitable movable armature engaging the inner wall of the tubular member to .be worked so that the device may be used in working non-magnetic materials. Since the construction shown in Figs. 5 and 6 is substantially the same generally as the construction shown i-n Figs. 1, 2, and 3, the same numerals will be used to indicate corresponding parts with the sufiix a added thereto. .As shown in Figs. 5 and 6, I provide gauge boxes 21a and 28a, substantially similar to the gauge boxes 21 and 20, and since the gauge boxes 21a and 28a are identical with each other, only vthe gauge box 21a will be described. The gauge box 21a is provided with a closure member 34a suitably secured relative to the gauge box and having provided therein an armature opening |00 through which the outer end |0| of an armature |02 extends, the armature |02 being formed of magnetic material. On the armature |02 is formed a block member |03 having attached thereto a U-shaped spring |04-which is secured to one end wall oi the gauge box 21a by suitable bolts |05, so as to support the armature for substantially axial movement.

A coil spring |06 is provided between the inside leg of the U-shaped spring |04 and the inner wall of the gauge box 21a so as to normally urge the armature |02 outwardly through the armature opening |00, a stop screw |01 being provided to limit outward movement of the armature by engagement with the outer leg of the U-shaped spring |04. Suitably positioned in the gauge box 2laris a core |08 formed of magnetic material and of U-shape, having an outer leg |09 and an inner leg I0 longer than the outer leg by approximately the dimension of the armature |02, providing a kiixed air gap and a variable air gap ||2 between the outer and inner legs |09 and H0, respectively, of the core |08 and the armature |02. Provided on the core |08 is a i'lrst winding ||3 connected in series with a second winding ||4 in the gauge box 28a by a conductor a, the outer end of the first winding being connected to a lead-in wire 31a and the outer end of the second winding being connected to a leadin wire 38a, so as to connect in series the iirst and second windings. As will be noted, the conductor 36a and the lead-in wire 38a pass through a slot'l I5 formed in a central portion ||6 of the plunger member 44a between the longitudinal channels 46a.

Hone boxes |9a are provided in the head member |3a similar to the hone vboxes I9, and are provided with hone elements 2|a adapted to engage the bore ||a of the tubular member |0a, as described in connection with Figs. 1, 2, and 3, the hone boxes |9a being moved radially outwardly by axial movement of the plunger member 44a as previously described.

In operation of the embodiment shown in Figs. 5 and 6, as the honing by means of the hone elements 2|a progresses, the armatures |02 will move outwardly in response to the action oi the coil springs |00 on the U-shaped spring |04 to increase the space between the inner end oi the `distance across the air gap ||2, the reluctance of such magnetic path will increase and the impedance oi! the winding ||3 will vary proportionally. Since the windings ||3 Yand ||4 are series-connected, it will be clear that the elctrical circuit shown in Fig. 4 may be utilized in the same manner as described hereinabove to indicate on the galvanometer variations in the diameter of the bore ||a due to the honing operation, it being evident that the windings ||3 and ||4 are substituted for the windings 26 and 35, respectively, shown in Fig. 4.

Throughout the foregoing specification I have referred to the operation of my device as a hon-I ing operation for the purpose of illustration, but it will be appreciated by those skilled in the art that the invention may equally well be utilized in grinding or other similar operations. Consequently, I hereby dene, for the purpose of this speciiication and the claims attached hereto, that the term honing as used herein shall mean honing, grinding, boring, or other method of removing material from a member to be worked.

Although I have shown and described a preferred form of my device, and an alternative embodiment, it will be appreciated that certain parts and units thereof, and of the electrical circuit shown in Fig. 4, are merely equivalents of certain other parts or elements which may be substituted therefor without the exercise of invention, and accordingly I do not intend to be limited to the disclosure herein, but wish to be afforded the full scope of the following claim.

I claim as my invention:

In a gauge device adapted to indicate a dimension of a member, the combnation of: a head element; a first gauge element including a iirst coil, said rst gauge element being so constructed and arranged that a variation in the distance of said iirst coil from one side of the member Varies the electrical impedance of said first col; rst box means containing saidfirst gauge element and removably secured to said head element; a second gauge element including a second coil, said second gauge element being so constructed and arranged that a variation in the distance of said second coil from the other side of the member varies the electrical impedance of said second coil, said coils being connected in series so that upon lateral movement of said head element relative to said member the impedance of said coils will vary by amounts that are equal and oppos'te; second box means containing said second gauge element and removably secured to said head element; means for impressing an electric potential across both said coils; and indicating means for measuring changes in the total im- RICARDO MESTAS. 

